Re: [9fans] MirOS ksh (mksh) building out-of-the box on Plan9/APE

[Jens Staal <staal1978@gmail.com>]

On Fri, 26 Jul 2013 13:01:16 -0400
erik quanstrom <quanstro@quanstro.net> wrote:

> On Fri Jul 26 12:30:20 EDT 2013, cinap_lenrek@gmx.de wrote:
> > plan9 kernel doesnt send notes on process exit to the parent. i do
> > not see any trivial way to emulate SIGCHLD as ape might spawn also
> > native processes so we cannot just add code to ape to emit the
> > signal on exit.
> >
> > we might handle wait records in a separate process tho using the
> > devproc's wait file (that means also we would need to reimplement
> > the various wait functions in ape as one would get a Einuse error
> > on wait() when someone reads your wait file, ugh) and also generate
> > a signal.


Would it be interesting to know how the other mksh ports (I think
Syllable and Win32) implemented SIGCHLD emulation? I also saw after
some googling that some tests in Go had to be ignored due to SIGCHLD
issues on Plan9, so I guess there are more use-cases than this one.
Unfortunately I know too little to actually give input on the actual
solution - most of it will come out as hot air (which hopefully won't
stink...).

>
> we may also have to do this if we wish to support pthreads with
> processes. pthreads allow one thread to wait for the children started
> by a second thread.
>
> - erik
>

A native APE pthread implementation would be awesome! I have been using
Gnu Pth some, but getting a proper APE variant would be much more
preferrable :)